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[TowerTalk] 80' Oak

To: <towertalk@contesting.com>
Subject: [TowerTalk] 80' Oak
From: jbigham2@kc.rr.com (Gene Bigham)
Date: Tue Aug 5 12:13:01 2003
Hello George et al,
Excellent questions.  I did not consider the tree in my installation as 
absorption or degradation of signal.  Since I was utilizing 3.5 MHz I figured 
the tree was transparent to my antenna and RF.  Since I worked DX from all over 
the compass I was happy.  Some notes on the mechanics and an anecdotal story 
follow.
I used a fishing rod and reel to sling up a suitably heavy cheap socket from a 
ratchet set over the top of the tree, then removed the socket and attached a 
heavier nylon line to the fishing line.  To attach fishing line to the nylon I 
used a boy scout technique which is difficult to describe verbally but involves 
doubling the fishing line wrapping it upon itself and securing the free end in 
the loop protruding from under this wrap - this eliminates knots which can snag 
on branches) and hoisted the nylon line back over, at this point if a larger 
nylon line is desired repeat this process using the smaller nylon to pull the 
larger nylon.  Finally used the nylon line to pull my wire up over the top.  
The nylon line remained in place and was tied off with very low tension to a 
suitable springy branch (a screen door spring works well if attaching to solid 
tie off) to accommodate wind movement in the tree and remained in place 3 years 
with Midwest storms until needing repairs due to abrasion.  Proactive nylon 
line replacement annually can be accomplished by tying new line to old nylon at 
the tie off end and pulling the antenna down removing the old nylon and 
securing the new line to the antenna tip end and pulling it back into place.  
This eliminates further tree fishing technique.  Wire was insulated single 
strand solid household electrical wire.
I was not concerned if some of the wire was not completely vertical, and the 
mid section of the wire did come out away from the trunk through certain lower 
branches.  The bottom end of the wire then approached the trunk again (the 
whole vertical wire forming a lazy C) to the base insulator which was attached 
to the trunk using a deck screw into the trunk and was almost at ground level.  
The coax center attached to the wire going up into the tree, the braid to my 
ground radials laid random length as space provided on the ground in garden and 
not visible areas and buried in foot traffic and visible areas.  Further, I 
bonded all neighborhood chain link fences with aluminum brazing rods available 
for use with a propane torch and attached the ground system to these fences as 
well.
Using an MFJ analyzer I was able to resonate the wire easily by pruning the 
wire at the base, (if multiple wire verticals are in the near field be sure to 
ground them out when taking resonance measurements on the antenna of interest). 
 I had made sure the overall wire was longer than needed to start with and 
could loosen the nylon line tie off and allow the wire to be pulled at the 
insulator to cut off a few inches off the vertical wire at a time.
An anecdotal comment:  I tried to sling a heavy 19mm (metric since working on 
metric 75/80M radio waves) socket over the top of the tree with lighter weight 
nylon line attached to the socket.  I attempted this bolo style.  Well as Mr. 
Murphy would have it, the socket and nylon caught a branch on the way up at the 
35 foot level and swung around the offending branch several times and locked 
itself onto the branch at a fork in the branch.  Repeated yanking yielded no 
loosening of this predicament.  I decided to put my weight into it.  So I 
wrapped the nylon line around my substantial rear end and attempted to walk 
backwards to free the line and the socket from the branch with brute force.  I 
believe it was 5 or 6 steps backwards and the line was taught as piano wire 
when the branch snapped and freed the socket and line.  What I saw next was a 
19mm socket rocketing toward me at hypervelocity.  I was unable to avoid the 
inevitable collision with my upper chest!  It stung and I was glad it missed my 
head and thought all was well, after all, I had my line and socket back for 
another attempt.  Sad to say a few minutes later I noticed my stomach felt wet 
and looked down to see a rather large area of blood stained shirt.  The impact 
of the socket on my upper sternum had opened a 3 inch wound down to the bone 
which required sutures to repair.  The physician was amused by my tale of being 
shot with a 19mm socket whilst tree fishing for maple bass.  It took quite a 
few stitches to repair the wound, I am still repairing my ego!
KB0GU
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